1. Field of the Invention
The present invention relates to an image display system and an image processing device, and more particularly, to an image display system that displays different images on a plurality of display devices (display screens) and to an image processing device used in the image display system.
2. Description of the Related Art
In an electronic device (image display system) having a graphics display function such as a car navigation system and a portable game machine, a plurality of virtual sheets called layers to place images thereon are superposed or changed in order to add some element to or to change an image on a display device. Japanese Unexamined Patent Application Publication No. 2003-288071, for example, has disclosed an image processing device which reads a plurality of pieces of image data from a memory and synthesizes the read image data in a predetermined order for output, and an image display system using this image processing device.
In configuring an image display system that displays different images on, for example, two display devices by use of the conventional image processing device, the image display system need to include two sets of an image processing device including a circuit for reading image data from memories and a circuit for synthesizing the read image data, and memories for storing the image data, in association with the two display devices. This greatly increases the scale of the image display system as well as the manufacturing cost.